As you know, Remote Procedure Call (RPC) isn't a Microsoft Windows specific concept. The first implementations of RPC were made on UNIX systems in the eighties. This allowed machines to communicate with each other on a network, and it was even used as the basis for Network File System (NFS). The RPC implementation developed by Microsoft and used on Windows is DCE/RPC (Distributed Computing Environment / Remote Procedure Calls). DCE/RPC is only one of the many Interprocess Communications (IPC) mechanisms used in Windows.